Rating Component

I wanted to create a smooth transition to the Thank You page, and this is what I came up with. Any suggestions on how to do a smoother transition after you hit "SUBMIT"?

"rating" was the name of my div with the first state, and "thanks" is the second div. They both had a CSS property of transition: opacity 250ms;

rating.style.opacity = 0;
    rating.addEventListener("transitionend", function () {
      rating.classList.add("hidden");
      thanks.classList.remove("hidden");
      setTimeout(() => (thanks.style.opacity = 1));
    });